A model is a three-dimensional of a person/thing or of a proposed structure.
A mock up is a model or replica of a machine or structure, used for instructional or experimental purposes.
A prototype is a first or preliminary version of a device or vehicle from which other forms are developed.
1,2, and 3 point perspective, very useful.
Registration will assure that the colors of a linocut or other relief print will align perfectly.
